ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Springer  (49,746)
  • 1995-1999
  • 1980-1984
  • 1975-1979  (44,825)
  • 1925-1929  (4,921)
  • 1978  (44,825)
  • 1927  (4,921)
Collection
Years
  • 1995-1999
  • 1980-1984
  • 1975-1979  (44,825)
  • 1925-1929  (4,921)
Year
  • 101
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 98-107 
    ISSN: 1436-4646
    Keywords: Network Flows ; Equilibrium Trade ; Quadratic Programming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract When supply and demand curves for a single commodity are approximately linear in each ofN regions and interregional transportation costs are linear, then equilibrium trade flows can be computed by solving a quadratic program of special structure. An equilibrium trade flow exists in which the routes carrying positive flow form a forest, and this solution can be efficiently computed by a tree growing algorithm.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 102
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 125-125 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 103
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 126-126 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 104
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 170-185 
    ISSN: 1436-4646
    Keywords: Nonlinear Programming ; Pseudoconvexity ; Second order Characterizations ; Extended Hessians ; Bordered Determinants ; Quadratic Functions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract Second order characterizations for (strictly) pseudoconvex functions are derived in terms of extended Hessians and bordered determinants. Additional results are presented for quadratic functions.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 105
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 263-263 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 106
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 378-378 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 107
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 380-380 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 108
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 14 (1978), S. 381-381 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 109
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 87-91 
    ISSN: 1436-4646
    Keywords: Lagrange Multipliers ; Constrained Convex Optimization ; Kuhn—Tucker Theorem ; Duality
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract The duality theorem of linear programming is used to prove several results on convex optimization. This is done without using separating hyerplane theorems.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 110
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 110-113 
    ISSN: 1436-4646
    Keywords: Fixed Point Computation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract Conditions are presented which are necessary for the existence of a regular fixed point of aC 1 map.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 111
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 122-122 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 112
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 162-176 
    ISSN: 1436-4646
    Keywords: Mixed Integer Programming ; Knapsack Problem ; Branch and Bound Method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract The ordinary knapsack problem is to find the optimal combination of items to be packed in a knapsack under a single constraint on the total allowable resources, where all coefficients in the objective function and in the constraint are constant. In this paper, a generalized knapsack problem with coefficients depending on variable parameters is proposed and discussed. Developing an effective branch and bound algorithm for this problem, the concept of relaxation and the efficiency function introduced here will play important roles. Furthermore, a relation between the algorithm and the dynamic programming approach is discussed, and subsequently it will be shown that the ordinary 0–1 knapsack problem, the linear programming knapsack problem and the single constrained linear programming problem with upper-bounded variables are special cases of the interested problem. Finally, practical applications of the problem and its computational experiences will be shown.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 113
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 211-213 
    ISSN: 1436-4646
    Keywords: Traveling Salesman Problem ; Cardinality Constraints ; Hamiltonian Circuits ; Network Flow Problems
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract The classic traveling salesman problem is characterized in terms of continuous flows on a specially constructed non-conservative network, in 2n − 1 linear constraints and a cardinality constraint. It is shown that every solution to the network problem is a hamiltonian circuit.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 114
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 220-222 
    ISSN: 1436-4646
    Keywords: Dynamic Decision Model ; Monotone Optimal Decision Functions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract The purpose of this short note is to correct some oversights in [1]. More precisely, we point out that stronger assumptions have to be imposed on the decision model (in order to use results in [2]) and present a counterexample to a comment to [1, Theorem 3.1].
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 115
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 239-242 
    ISSN: 1436-4646
    Keywords: Minimax Optimization ; Nonlinear Programming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract An unconstrained minimax algorithm of Charalambous and Conn is easily modified to solve the constrained case. Here we present some numerical results and find that this algorithm compares favourably to those of Dutta and Vidyasagar.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 116
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 247-260 
    ISSN: 1436-4646
    Keywords: Quasi-Newton Method ; Optimal Conditioning ; Rank-two Update
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract Davidon's new quasi-Newton optimization algorithm selects the new inverse Hessian approximation $$\bar H$$ at each step to be the “optimally conditioned” member of a certain one-parameter class of rank two updates to the last inverse Hessian approximationH. In this paper we show that virtually the same goals of conditioning can be achieved while restricting $$\bar H$$ to the convex class of updates, which are bounded by the popular DFP and BFGS updates. This suggests the computational testing of alternatives to the “optimal conditioning” strategy.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 117
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 261-267 
    ISSN: 1436-4646
    Keywords: Sensitivity Analysis in Nonlinear Programming ; Computational Aspects ; Chemical Equilibrium Problems ; Entropy Maximization Problems
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract This paper presents an implementation of some recent results of Bigelow and Shapiro [1]. These implicit function theorems are shown to provide a convenient means of performing certain types of sensitivity analysis, in particular updating the lagrange multipliers, associated with particular classes of problems. As a result we extend the usual sensitivity analysis results to include improving estimates of the effect of changing the right-hand sides of constraints. Examples of chemical equilibrium and entropy maximization models are used to illustrate the results.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 118
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 278-290 
    ISSN: 1436-4646
    Keywords: Constrained Optimization ; Exact Penalty Functions ; Nondifferentiable Functions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract The purpose of this paper is to present new exact penalty functions and discuss their properties. A lower bound on the controlling parameters is given, for which above this value, the optimum of the exact penalty function coincides with the optimum of the nonlinear programming problem.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 119
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 291-314 
    ISSN: 1436-4646
    Keywords: Network Flow Problems ; Computational Results—Efficiency—Comparison ; Specific problems in mathematical programming ; Computational Experiments ; Pivotal Selection Methods ; Starting Strategies ; Scaling Procedure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract This paper describes the experimental results of testing a “large-scale” program for solving minimum-cost network flow problems. With this program, general structure transshipment problems with over ten thousand nodes and thirty thousand arcs have been easily solved without resorting to auxiliary storage. The algorithm is a variant of the primal revised simplex method; the computer code is called LPNET illustrating the close connection between linear programming and network graphs. This approach substantially improves computer processing timeand core storage, especially for relatively large network problems. The results of these experiments are provided. It is emphasized that an organized experimental design and a detailed series of empirical tests are crucial for an efficient implementation.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 120
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 360-362 
    ISSN: 1436-4646
    Keywords: Nonlinear Decomposition ; Nonlinear Programming
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract We show that under certain conditions nonlinear programming problems can be decomposed into a series of smaller problems. A Decomposition Theorem and example are presented.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 121
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 363-363 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 122
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 365-368 
    ISSN: 1436-4646
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 123
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 26-35 
    ISSN: 1436-4646
    Keywords: Manpower Planning ; Column Generation ; Network Flows ; Shortest Path ; System Design
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract An equilibrium model of a manpower system is developed based on the notion of a career flow. Institutional constraints and measures of system performance are linear functions of the career flow. A typical optimal design problem is formulated and a solution procedure is developed. The optimization problem is a generalized linear program in which columns are generated by solving a shortest path problem. Upper and lower bounds on the optimal value function can be developed at each stage of the calculations.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 124
    Electronic Resource
    Electronic Resource
    Springer
    Mathematical programming 15 (1978), S. 53-62 
    ISSN: 1436-4646
    Keywords: Convex Program ; Decomposition ; Cutting Plane Algorithm ; Stochastic Quadratic Program with Recourse
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Mathematics
    Notes: Abstract A piecewise convex program is a convex program such that the constraint set can be decomposed in a finite number of closed convex sets, called the cells of the decomposition, and such that on each of these cells the objective function can be described by a continuously differentiable convex function. In a first part, a cutting hyperplane method is proposed, which successively considers the various cells of the decomposition, checks whether the cell contains an optimal solution to the problem, and, if not, imposes a convexity cut which rejects the whole cell from the feasibility region. This elimination, which is basically a dual decomposition method but with an efficient use of the specific structure of the problem is shown to be finitely convergent. The second part of this paper is devoted to the study of some special cases of piecewise convex program and in particular the piecewise quadratic program having a polyhedral constraint set. Such a program arises naturally in stochastic quadratic programming with recourse, which is the subject of the last section.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 125
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract We develop a new iteration scheme giving bounds for the positive eigenvector of a nonnegative and irreducible matrix and the corresponding eigenvalue and test it on some examples.
    Notes: Zusammenfassung Wir geben ein neues Iterationsverfahren an, das Schranken für den positiven Eigenvektor einer nichtnegativen, irreduziblen Matrix und des zugehörigen Eigenwerts liefert.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 126
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 17-26 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract Due to the free parameter in the fixed-point equation of the parallel-chord-method, it is possible to reduce the Lipschitz constant of the contraction mapping. By use of this reduction, it is possible in suitable cases to generate the contraction property of the mapping. If the mapping possesses this property, then this is also true for the mapping with the parameter determined here. In addition, both an improved error estimate for the sequences of iterates and a smaller convergence factor are obtained. An example is presented.
    Notes: Zusammenfassung Mit Hilfe des freien Parameters in der Fixpunktgleichung des Parallelenverfahrens ist es möglich, die Lipschitz-Konstante der kontrahierenden Abbildung zu verkleinern. Durch diese Verkleinerung kann in geeigneten Fällen eine kontrahierende Abbildung erzeugt werden. Ist die Abbildung bereits kontrahierend, ist sie auch kontrahierend für den berechneten Wert des Parameters. Ferner ergibt sich neben einer verbesserten Fehlerabschätzung für die Iterationsfolgen auch ein kleinerer Konvergenzfaktor. Das Verfahren wird an Hand eines Beispiels erläutert.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 127
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 75-94 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract A theory of hybrid finite element approximation is developed for a class of shell problems. Though it is applied only to the special case of clamped shallow shells with regular triangularization the results may be of larger interest comparing the predicted convergence rate with the numerical outcome of some applications of the hybrid finite element method. The convergence speed can only be increased by higher degrees of the approximation and the stresses at the edges correspondingly. The use of a so-called rank condition plays a fundamental role in the study. Weak coerciveness of the under lyigg bilinear form for the derivation of hybrid elements is proved by showing the existence of a stationary point.
    Notes: Zusammenfassung Dieser Beitrag liefert eine Theorie der Finite-Element-Approximation für eine Klasse von Schalenproblemen. Obgleich diese nur für den Fall der eingespannten flachen Schale mit regulärer Triangulierung ausführlich dargestellt wird, sind die Ergebnisse darüberhinaus von Interesse, da die abgeleiteten Konvergenzordnungen das Verhalten numerischer Näherungslösungen aus anderen Anwendungen der hybriden Finite-Element-Methode erklären helfen. Die Konvergenzgeschwindigkeit kann nur verbessert werden durch gleichzeitige Erhöhung der Ansatzgrade für die Verschiebungen im Elementinnern und für die Spannungen auf den Rändern. Die Einhaltung einer sogenannten Rangbedingung hat zentrale Bedeutung. Die schwache Koerzitivität der für die Ableitung hybrider Elemente verwendeten Bilinearform ist durch den Nachweis der Existenz eines stationären Werts gesichert.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 128
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 153-163 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Eine verbesserte Darstellung Newtonscher Intervall-Verfahren wird diskutiert. Es wird dabei gezeigt, daß man bestimmte Intervalle in den Verfahren durch reelle Zahlen ersetzen kann. Dadurch werden die Konvergenzeigenschaften der Verfahren verbessert.
    Notes: Abstract Improved forms of some interval Newton Methods are given. It is shown that certain intervals in the methods can be replaced by real numbers. This improves the convergence properties of the methods.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 129
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 177-182 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract The bound of Prager-Oettli for the input error of a linear system of equations is computed via a new formula which guarantees strictness of the bound in spite of roundoff errors.
    Notes: Zusammenfassung Die Schranke von Prager-Oettli für den Eingangsfehler eines linearen Gleichungssystems wird über eine neue Formel berechnet, die trotz der Rundungsfehler die Schärfe der Schranke sichert.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 130
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 207-228 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Die Iterierte Defektkorrektur (IDeC) ist ein Verfahren zur schrittweisen Verbesserung einer Näherungslösung eines gegebenen ProblemsFy=0. Eines der wichtigsten Anwendungsgebiete dieses Prinzips sind Differentialgleichungen. Die IDeC kann dort als Methode zur Verbesserung der Ordnung eines Diskretisierungsverfahrens, und damit zur Verbesserung der Genauigkeit eingesetzt werden. In der vorliegenden Arbeit wird ein Metaalgorithmus für die Klasse, der IDeC-Verfahren für Differential-gleichungen vorgestellt und analysiert. Für jeden “Baustein” dieses Metaalgorithmus werden Bedingungen angegeben, die es gewährleisten, daß eine bestimmte Ordnung erreicht wird. Diese Bedingungen sind von großer praktischer Bedeutung, wenn IDeC-Verfahren als Computer-Programme implementiert werden sollen.
    Notes: Abstract Iterated Defect Correction (IDeC) is a technique for improving successively an approximate solution of a given problemFy=0. One of the most important fields of application of this principle are differential equations. Here, IDeC can be used as a technique for increasing the order of a discretization method and thus for improving the accuracy. In this paper a metalgorithm for the class of IDeC-methods for differential equations is presented and analyzed. For every component of this metalgorithm conditions are given which guarantee a certain order of accuracy. These conditions are of particular importance for practical applications, as far as the implementation of IDeC-methods is concerned.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 131
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 257-265 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract A termination criterion by Nickel (Theorem 6, [1]) for guaranteeing the numerical convergence for locally stable and consistent algorithms is generalized. The assumption |x ν+2,x ν+1|≤L|x ν+1,x ν| (0≤L〈1,L real constant) of the approximation sequence {x ν} to the solution is replaced by the convergence of the progression $$\sum\limits_{v = 1}^\infty {|x,x_{v + 1} |/Q^v (0〈 Q〈 1)} $$ . Therefore the theorem of this paper is applicable to a large number of numerical procedures, for which untill now no termination criterion has been known (for example: Rombergprocedure). In particular this weakening is important for the computation of approximation solutions for integral equations.
    Notes: Zusammenfassung Ein Abbrechkriterium von Nickel (Satz 6, [1]) zur Sicherung der numerischen Konvergenz bei lokal stabilen und konsistenten Algorithmen wird verallgemeinert. Statt der Eigenschaft |x ν+2,x ν+1|≤L|x ν+1,x ν| (0≤L〈1,L von ν ∈ ℕ unabhängig) der Näherungsfolge {x ν} zur Lösungx reicht die Konvergenz der Reihe $$\sum\limits_{v = 1}^\infty {|x,x_{v + 1} |/Q^v (0〈 Q〈 1)} $$ aus. Damit ist der Satz dieser Arbeit bei einer großen Klasse von numerischen Verfahren anwendbar, für die bisher noch kein Abbrechkriterium bekannt ist (z. B. dem Romberg-Verfahren). Insbesondere ist diese Abschwächung zur Berechnung von Näherungslösungen bei Integralgleichungen wichtig.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 132
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 307-324 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Ausgehend von einem Existenz- und Eindeutigkeitssatz für die Lösung einer verallgemeinerten Volterra-Integralgleichung zweiter Art wird die Existenz und Eindeutigkeit der Lösung der hier behandelten nichtlinearen, schwach singulären Volterra-Integralgleichung erster Art untersucht. Es wird ein numerisches Verfahren der Ordnung 2 bzw. 3 angegeben. Der Konvergenzbeweis basiert in beiden Fällen auf einem Lemma über die Beschränktheit einer speziellen Differenzenungleichung. An zwei numerischen Beispielen werden die theoretischen Ergebnisse demonstriert.
    Notes: Abstract Starting from an existence and uniqueness theorem for a generalized nonsingular second kind Volterra equation existence and uniqueness for the solution of the nonlinear, weakly singular first kind Volterra equation is examined. A new type of numerical method is developed. A basic lemma concerning the boundedness of a special difference inequality is given and order two or three convergence of the method is shown. Two numerical examples illustrate the theoretical results.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 133
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 343-350 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract For each α ε (0, π/2), the existence ofA (α)-stable linear multistep methods with arbitrary order of consistency is shown by an explicit construction. Some characteristic data of the methods and numerical results are given.
    Notes: Zusammenfassung Es wird in einer expliziten Konstruktion gezeigt, daß für jedes α ε (0, π/2)A (α)-stabile lineare Mehrschrittverfahren beliebiger Konsistenzordnung existieren. Einige charakteristische Daten der Verfahren und numerische Rechnungen werden angegeben.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 134
    Electronic Resource
    Electronic Resource
    Springer
    Computing 21 (1978), S. 17-35 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Der Ansatz, Strings, die zusammengemischt werden, auf Magnetplatten vorzuplanen, wird unter Leistungsgesichtspunkten untersucht. Konzepte für die interne Pufferzuordnung, für die Erzeugung der anfänglichen Strings durch ein internes Sortierverfahren, und für die Stringverteilung auf Magnetplatten werden ausgewertet. Ein Algorithmus beschreibt die Konstruktion von suboptimalen Mischbäumen, die planbare Mischbäume genannt werden. Ein Kostenmodell, das auf detaillierte Annahmen der Zuordnung vonk Eingabeplatten und der Planung einesr-Wege-Mischens beruht, wird für das exakte Vorplanen aufgestellt. Zeitbetrachtungen für Sortieren und Mischen, die Hardware-Eigenschaften von Magnetplatten einschließen, zeigen signifikante Zeitgewinne verglichen mit weitverbreiteten Sortier- und Mischverfahren.
    Notes: Abstract The idea of preplanning strings on disks which are merged together is investigated from a performance point of view. Schemes of internal buffer allocation, initial string creation by an internal sort, and string distribution on disks are evaluated. An algorithm is given for the construction of suboptimal merge trees called plannable merge trees. A cost model is presented for accurate preplanning which consists of detailed assumptions on disk allocation fork input disks andr-way merge planning. Timing considerations for sort and merge including hardware characteristics of moveable head disks show a significant gain of time compared to widely used sort/merge applications.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 135
    Electronic Resource
    Electronic Resource
    Springer
    Computing 21 (1978), S. 53-69 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung In dieser Arbeit werden mehrere effiziente Methoden zur Berechnung von Funktionen, die durch Potenzenreihen definiert sind, präsentiert. Einfache Computerprogramme für zwei schnelle Algorithmen werden in einem eigenen Beitrag ([9]) angegeben. Die Konvergenzgeschwindigkeiten der vorgeschlagenen Verfahren werden theoretisch untersucht und die erhaltenen Ergebnisse werden an numerischen Beispielen erläutert.
    Notes: Abstract In this paper we present several efficient methods for evaluating functions defined by power series expansions. Simple computer codes for two rapid algorithms are given in a companion paper. The convergence rates of the proposed computational schemes are investigated theoretically and the results are illustrated by numerical examples.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 136
    Electronic Resource
    Electronic Resource
    Springer
    Computing 21 (1978), S. 71-79 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Mit Hilfe der Pseudoinversen eines beschränkten linearen Operators von ℝ n inl 2 wird eine Methode zur Konstruktion von Quadraturformeln für die Integration über einem beliebigen beschränktenm-dimensionalen GebietB⊂ℝ m hergeleitet, mit der Eigenschaft, daß der mittlere Fehler in einer vorgeschriebenen FamilieF sowie die Varianz der Rundungsfehler gemäß Sard [8] minimal werden. Sodann wählen wirF als gewichtete Monome und behandeln als Beispiel Integration auf der Oberfläche derm-Kugel.
    Notes: Abstract Using the concept of the generalized inverse of a bounded linear transformation between ℝ n andl 2, a method is given for constructing quadrature rules for integration over an arbitrary boundedm-dimensional regionB⊂ℝ m with the property that the average error over the prescribed familyF of the functions continuous inB as well as the variance of the rounding errors according to Sard [8] are minimal. Then we specializeF to the weighted monomials and treat as an example integration on the surface of them-sphere.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 137
    Electronic Resource
    Electronic Resource
    Springer
    Computing 21 (1978), S. 87-91 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung In dieser Arbeit werden zwei Computerprogramme für die Berechnung der Summe einer Potenzenreihe, die einer allgemeinen Klasse zugehört, beschrieben. Die Verwendung der Programme ist mit einem Beispiel erläutert.
    Notes: Abstract This paper describes two computer codes for calculating the sum of power series, belonging to a certain general class. The use of the codes for an illustrative test example is explained.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 138
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 1-16 
    ISSN: 1436-5057
    Keywords: Integration ; Runge-Kutta integration ; truncation error ; error estimates ; accumulated error ; accumulated error estimates ; accumulated truncation error ; true error
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Es wird eine Methode für die Entwicklung von Runge-Kutta-Integrationsalgorithmen angegeben, die die Schätzung des globalen Verfahrensfehlers ermöglichen. Mehrere neue Algorithmen 2., 3. und 4. Ordnung werden angeführt. Die Rechenarbeit pro Schritt ist identisch für die neuen Algorithmen und für Algorithmen, die nur eine Schätzung des lokalen Verfahrensfehlers ermöglichen. Numerische Versuche mit den neuen Algorithmen ergeben, daß der geschätzte Fehler den wahren akkumulierten Fehler gut wiedergibt. Außerdem ist der Fehler von derselben Ordnung wie bei gewöhnlichen Runge-Kutta-Algorithmen.
    Notes: Abstract A method is presented for developing Runge-Kutta integration algorithms with built-in estimates of the accumulated truncation error. Several new 2-nd, 3-rd, and 4-th order algorithms are given. The computation per step of the new algorithms is identical to that of algorithms which provide only an estimate of the local truncation error. Numerical experimentation with the new algorithms shows that the estimated error compares very well with the true accumulated error. Further, the error is of the same order as that incurred using traditional Runge-Kutta algorithms.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 139
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 47-60 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Das Anfangsrandwertproblem für die hyperbolische Differentialgleichunga(t,x,u)u tt +2b(t,x,u)u tx +c(t,x,u)u xx =d(t,x,u,u t ,u x ) zweiter Ordnung wird mit Hilfe eines Charakteristikenverfahrens gelöst, das keine Differenzengleichungen füru t undu x benutzt. Die Lösung des diskretisierten Problems besitzt eine asymptotische Entwicklung nach geraden Potenzen der Schrittweite. Daher können die numerischen Ergebnisse durch Extrapolation verbessert werden.
    Notes: Abstract The hyperbolic initial-boundary value problem for the second order equationa(t,x,u)u tt +2b(t,x,u)u tx +c(t,x,u)u xx =d(t,x,u,u t ,u x ) is solved by a special method of characteristics involving no difference equations foru t andu x . The discrete solution has an asymptotic expansion in even powers of the step size. Therefore, the numerical results can be improved by extrapolation to the limit.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 140
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 165-176 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Das folgende Problem wird behandelt: gegeben sei eine Menge vonm rechteckigen Gebieten in der Ebene, man finde ein Intervall-Polynom vom Gradn〉m durch diese Gebiete. Dies ist eine Verallgemeinerung des diskreten Problems der kleinsten Quadrate. Drei Verallgemeinerungen der gewöhnlichen Methode der kleinsten Quadrate für Polynome werden betrachtet und an numerischen Beispielen verglichen. Eine dieser Methoden wird empfohlen, da sie in allen Testbeispielen bessere Ergebnisse gibt.
    Notes: Abstract The following problem is treated: given a set ofm rectangular regions in the plane, fit an interval polynomial of degreen〉m through the regions. This is a generalization of the discrete polynomial least squares problem. Three generalizations of the standard methods for the discrete polynomial least squares are considered and compared on numerical examples. One of the methods is recommended since it gives superior results in all cases tested.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 141
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 189-205 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Eines der am besten beschriebenen Modelle kombinatorischer Optimierung ist das Scheduling Problem, bei dem eine endliche Anzahl von Tätigkeiten auf einer festen Anzahl von Maschinen so ausgeführt werden muß, daß eine gegebene Zielfunktion minimiert wird. Jede Tätigkeit benötigt charakteristische Daten wie Bearbeitungszeit, Fertigsteillungstermin, Strafkosten und technologische Nachfolgebeziehungen. Ein algebraischer Ansatz für die Zielfunktion führt zu einem allgemeinen Problem, das alle in der Literatur bekannten klassischen Fälle von Summen und Maximum Zielfunktionen einschließt. Durch die Lösung eines algebraischen Transportproblems wird eine untere Schranke für den Zielfunktionswert bestimmt. Um eine Optimallösung zu erhalten, verwenden wir ein Branch and Bound Verfahren. Weiterhin betrachten wir das allgemeine Job Shop Scheduling Problem mit algebraischer Zielfunktion.
    Notes: Abstract One of the well-studied models of combinatorial optimization is the scheduling problem dealing with a finite set of tasks, which have to be executed on a fixed number of machines so that a given objective is minimized. Each task requires a set of characteristic data like operating time, due date, penalty cost and technological requirements. An algebraic approach to the objective leads to a general problem which includes all classical cases of sum and bottleneck objectives known in literature. By solving an algebraic transportation problem a lower bound for the objective value can be determined. To obtain an optimal solution we employ a branch and bound procedure. Furthermore we consider the general job shop scheduling problem with algebraic objective function.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 142
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 325-331 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract The result of this paper is the economizing of cpu-time by identical guaranteed precision of the approximate solution. This is possible by an optimal selection ofn j in every iteration stepj, wheren j is the number of subintervals for the numerical integration. The determination ofn 1,n 2, ... is reduced to the solution of a solvable convex optimization job.
    Notes: Zusammenfassung Es wird die Einsparung von Rechenzeit bei gleicher garantierter Genauigkeit der Näherungslösung ermöglicht. Dies wird erreicht durch eine optimale Wahl vonn j bei jedem Iterationsschrittj, wobein j die Zahl der Teilintervalle für die Quadratur ist. Die Bestimmung vonn 1,n 2,... wird auf die Lösung einer lösbaren konvexen Optimierungsaufgabe zurückgeführt.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 143
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 279-290 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract It is one of the basic questions in designing a database system to determine which attributes to invert. The literature presents a variety of models to solve this question. This paper attempts to give a guideline, under which conditions a primitive model considering only retrieve operations, suffices to determine an optimal solution. The relevance of that question lies in the smaller costs of simpler models.
    Notes: Zusammenfassung Eine wesentliche Fragestellung beim Aufbau eines Datenbanksystems ist die Auswahl der Schlüsselattribute. Bei Inverted-File Systemen ist dies äquivalent zur Auswahl der zu invertierenden Attribute. In diesem Aufsatz wird versucht darzustellen, unter welchen Bedingungen Modelle, die lediglich das Retrieve-Verhalten des Benutzers berücksichtigen, zuverlässige Resultate liefern können. Die Relevanz dieser Fragestellung liegt vor allem in den durch das einfachere Modell verminderten Kosten der Datenbeschaffung und Datenanalyse im DB-Designprozeß.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 144
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 351-361 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Es wird ein allgemeines, quasilineares, nichtstationäresk-Schrittverfahren für die Lösung des Cauchy-Problems für gewöhnliche Differentialgleichungen untersucht. Ein Konvergenzsatz mit ziemlich schwachen Bedingungen wird angegeben. Die Inkrementfunktion muß nicht Lipschitz-stetig sein; es genügt, wenn diese Funktion die Perron-Bedingung aus der Eindeutigkeitstheorie für das Cauchy-Problem mit nichtabnehmender Vergleichfunktion erfüllt. Das Ergebnis ist eine Erweiterung der Theorie von G. Dahlquist und des letzten Resultats von K. Taubert.
    Notes: Abstract The general form of a quasilinear nonstationaryk-step method for solving of the Cauchy problem for ordinary differential equations is discussed. The convergence theorem is stated under rather weak conditions. It is not assumed that the increment function is Lipschitz-continuous but only that it satisfies the Perron type condition appearing in the uniqueness theory for the Cauchy problem with a nondecreasing comparison function. The result established in the paper is an extension of the theory given by G. Dahlquist and the recent result of K. Taubert.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 145
    Electronic Resource
    Electronic Resource
    Springer
    Computing 20 (1978), S. 363-375 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Hier wird ein neuer selbsteichender Algorithmus für die Integration der analytischen Funktionen dargestellt. Der Algorithmus wirkt auf das Integrationsintervall indem er örtliche Unterintervalle hervorruft, deren Länge durch ein neues System überwacht wird. Die Überwachung ergibt sich aus einer Formel, die von einer analytischen Basis abgeleitet wird und für jede beliebige Integrationsregel gilt: mit zwei verschiedenen Annäherungen eines Integrals wird die Intervallänge berechnet, die notwendig ist, um eine Integralannäherung mit der innerhalb zugelassener Fehlergrenzen notwendigen Genauigkeit zu erreichen. Die daraus entstehende Methode für die Erzeugung der Unterintervalle und eine wirksame Auswahl der Fehlerverteilung unter die Unterintervalle bringen einen selbstanpassenden Algorithmus hervor, der über einen genauen und höchst günstigen Integrationsprozeß verfügt. Darauf wird der besondere Algorithmus betrachtet, der sich mit Hilfe der 6-Punkte-Gauß-Legendre-Integrationsregel ergibt. Außerdem wird er mit den besten unter den anderen Integrationsalgorithmen verglichen.
    Notes: Abstract A new adaptive algorithm for the integration of analytic functions is presented. The algorithm processes the integration interval by generating local subintervals whose length is controlled through a feedback loop. Control is performed by means of a relation derived on an analytical basis and valid for an arbitrary integration rule: two different estimates of an integral are used to compute the interval length necessary to obtain an integral estimate with accuracy within the assigned error bounds. The implied method for local generation of subintervals and an effective assumption of error partition among subintervals give rise to an adaptive algorithm provided with an accurate and very efficient integration process. The particular algorithm obtained by choosing the 6-point Gauß-Legendre integration rule is considered and extensive comparisons are made with other outstanding integration algorithms.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 146
    Electronic Resource
    Electronic Resource
    Springer
    Computing 21 (1978), S. 37-52 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Abstract Direct methods for the solution of linear approximation problems tend to fail in practice because of numerical instabilities. Difficulties arise from an undesired accumulation of round-off errors. In [3] and in chapter 2 of this paper effective and inexpensive tests are developed to recognize numerical difficulties and stabilize numerical methods by iterative refinement and restart procedures, if necessary. On the ground of this, a stabilized version of a modified revised dual simplex algorithm can be developed capable of solving the approximation problems under consideration. The technical details of this method and a FORTRAN implementation are given in [4]. Numerical examples are discussed to illustrate that the developed method is superior to commonly used algorithms not only by a broader range of applications and more stability, but also by considerably less storage requirement (for large problems), while the execution times are comparable or less.
    Notes: Zusammenfassung Anhäufungen von Rundungsfehlern führen in der Praxis häufig dazu, daß direkte simplexartige Methoden zur Lösung linearer Approximationsprobleme in der Maximumsnorm versagen. Vor dem approximationstheoretischen Hintergrund des Problems werden in der vorliegenden Arbeit einfach durchzuführende Tests entwickelt, die numerische Schwierigkeitenim voraus anzeigen und so Gegenmaßnahmen ermöglichen. Anhand einer Reihe von Beispielen werden Stabilität, Anwendungsbereich und Grenzen darauf aufbauender Algorithmen diskutiert.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 147
    Electronic Resource
    Electronic Resource
    Springer
    Computing 21 (1978), S. 81-86 
    ISSN: 1436-5057
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science
    Description / Table of Contents: Zusammenfassung Für das „0–1 single Knapsack Problem” wird eine FORTRAN-Implementierung eines wirkungsvollen Lösungsverfahrens angegeben. Die angeführten Rechenergebnisse zeigen, daß die vorgeschlagene Methode den derzeit besten bekannten Algorithmen überlegen ist.
    Notes: Abstract The FORTRAN implementation of an efficient algorithm which solves the 0–1 single knapsack problem is given. Computational results are presented, showing the proposed method to be generally superior to the best known algorithms.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 148
    Electronic Resource
    Electronic Resource
    Springer
    European journal of nutrition 17 (1978), S. 124-127 
    ISSN: 1436-6215
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 149
    Electronic Resource
    Electronic Resource
    Springer
    European journal of nutrition 17 (1978), S. 129-139 
    ISSN: 1436-6215
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary Since most of the drugs are taken orally via the gastrointestinal tract, interactions with food ingredients may lead to alterations in the intake of essential dietary factors. With regard to vitamins the following effects have been demonstrated: early decomposition resp. inactivation, decreased absorption or a qualitatively and quantitatively modified metabolism. Examples of such changes are given with regard to water- and lipid-soluble vitamins.
    Notes: Zusammenfassung Arzneimittel werden meistens peroral, d. h. über den Magen-Darm-Kanal, zugeführt. Damit besteht die Möglichkeit einer Interaktion mit Nahrungsinhaltsstoffen, die aber dann bedeutsam sein dürfte, wenn essentielle Nahrungsfaktoren wie z. B. Vitamine betroffen sind. Für die Vitamine können sich dann folgende Auswirkungen ergeben: eine vorzeitige Zerstörung bzw. Inaktivierung, eine gehemmte Resorption aus dem Magen-Darm-Kanal oder eine quantitativ und qualitativ veränderte Metabolisierung. Anhand von Beispielen werden derartige Auswirkungen von Arzneimitteln auf wasserlösliche und fettlösliche Vitamine aufgezeigt.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 150
    Electronic Resource
    Electronic Resource
    Springer
    European journal of nutrition 17 (1978), S. 112-123 
    ISSN: 1436-6215
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary Mould cultures are used for the manufacture of soft and blue cheese. The report deals with the present stage of knowledge of the question of mycotoxin-producers in mould cultures used for cheesemaking. The PR-toxin was isolated repeatedly fromPenicillium roqueforti strains which were incubated on special media, but also from P. roqueforti cultures used for cheese manufacture. However, cheese ripening conditions do not favow the production of this toxin. Other catabolites from P. roqueforti such als roquefortine and isofumigaclavine have been found in cheese, but there is not much known about their toxic effect. No cancerogenic mycotoxins have been discovered in these types of cheese, except aflatoxin M1 which might however originate from contaminated milk. It must be concluded that the occurrence of tumors after feeding of a pureP. camemberti var. candidum culture is due to the effect of mycotoxins. On the other hand, further animal experiments with various mould culture strains used for cheesemaking have not confirmed these findings. On the basis of the literature consulted it may be said that the use of mould cultures for cheesemaking does not involve any risk for human health, that means it is toxicologically harmless.
    Notes: Zusammenfassung Schimmelpilzkulturen werden bei der Herstellung von Weißschimmel— und Blauschimmelkäse verwendet. Es wird über den gegenwärtigen Stand der Kenntnisse zur Frage von Mykotoxinbildnern in Schimmelpilzkulturen der Käsefabrikation berichtet. Verschiedentlich wurde ausPenicillium roqueforti-Stämmen, die auf speziellen Medien bebrütet wurden, das PR-Toxin isoliert, auch aus P. roqueforti-Kulturen, die zur Käseherstellung verwendet werden. Doch sind die Bedingungen der Käsereifung für eine Produktion dieses Toxins nicht geeignet. Weitere Stoffwechselprodukte von P. roqueforti wie Roquefortin und Isofumigaclavin konnten in Käse aufgefunden werden, doch ist über deren toxische Wirkung wenig bekannt. Kanzerogen wirkende Mykotoxine konnten in Schimmelkäsen nicht gefunden werden, außer Aflatoxin M1, das jedoch aus der kontaminierten Milch stammen dürfte. Das Auftreten von Tumoren nach Verfütterung einer Reinkultur vonP. camemberti var. candidum ließ auf eine Mykotoxinwirkung schließen. Doch haben weitere Tierversuche mit verschiedenen, bei der Käsefabrikation verwendeten Schimmelpilzstämmen diesen Befund nicht bestätigt. Es läßt sich aufgrund der gesichteten Literatur sagen, daß der Einsatz von Schimmelpilzkulturen in der Käsefabrikation kein Risiko für den Menschen darstellt, also toxikologisch unbedenklich ist.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 151
    ISSN: 1436-6215
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary After the 24 hours preoperative infusion period 0.37% glucose, 0.05% fruc tose and 1.28%xylitol of the infused amount were excreted in the urine. Postoperatively fructose was the best metabolized energy donator before xylitol and glucose. As a sign of an undisturbed hepatic synthesis of lipoproteins the triglycerides rose up to the 5th postoperative day. During the parenteral nutrition and the additional surgical intervention the cholesterol fell from 192.3 to 128.5 mg/100 ml on the first postoperative day. The infusion solutions caused a rise of the insulin concentration from 23.2 to 46.3 U/1 on the operation day. There is a positive nitrogen balance of 3.5 g/24 h on the operation day. The slight negative balance of −1.15 g/24 h on the first postoperative day is reduced to − 0.61 g/24 h on the postoperative day. The changes of the enzymes LDH, GOT and AP were at normal range. The postoperative changes were due to the surgical intervention. Without a simultaneous change of enzymes, 5 patients had a rise of bilirubin up to 1.1 mg/100 ml. To avoid a too great loos of phosphate during a long-term parenteral nutrition period, it is important to put up a balance.
    Notes: Zusammenfassung Nach 24stündiger präoperativer Infusionsperiode werden von der infundierten Menge 0,37% Glukose, 0,05% Fruktose und 1,28% Xylit im 24-h-Urin ausgeschieden. Postoperativ erweist sich Fruktose vor Xylit und Glukose als der am besten verwertete Energieträger. Als Zeichen einer ungestörten hepatischen Lipoproteinsynthese steigen die Triglyzeride bis zum 5. postoperativen Tag an. Unter der parenteralen Ernährung und durch den zusätzlichen operativen Eingriff erfolgt ein starker Cholesterinabfall von 192,3 auf 128,5 g/100 ml am 1. postoperativen Tag. Durch die Infusionslösungen steigt die Insulinkonzentration von 23,2 auf 46,3 U/1 am Operationstag an. Postoperativ werden erhöhte Insulinwerte gemessen. Die Harnsäurekonzentration fällt bis zum unteren Normbereich ab. Am Operationstag besteht eine positive N-Bilanz von 3,5 g/24 h. Die leicht negative Bilanz von −1,15 g/24 h am 1. postoperativen Tag geht bis zum 4. postoperativen Tag auf −0,61 g/24 h zurück. Die Veränderungen der gemessenen Enzyme LDH, GOT und AP bewegen sich im Normbereich. Die postoperativen Veränderungen sind auf den operativen Eingriff zurückzuführen. Ohne entsprechende Enzymveränderungen erfolgt bei 5 Patienten ein Anstieg der Bilirubinkonzentration auf 1,25 mg/100 ml. Um zu große endogene Phosphatverluste bei längerfristiger parenteraler Ernährung zu vermeiden, ist es notwendig, eine Bilanz aufzustellen.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 152
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 5-37 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Theq-Hahn polynomials appear as functions on the lattice of subspaces of a finite-dimensional vector space over a finite field. Irreducible representations of the related general linear group are restricted to a maximal parabolic subgroup, and a specific description of the resulting irreducible components leads to an addition formula.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 153
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 1-3 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract The following theorem is proved, based on an irrationality measure fore a (a∈0, rational) ofP. Bundschuh: Letp, q, u, v∈0 be rational integers withq≥1,v≥1,a=u/v, 0〈δ≤2. If $$\begin{gathered} q 〉 \exp \{ u^2 ((ea)^2 /8) (1 + u^2 (a e/2)^2 ) + |u|^{8/\delta } e^{2/\delta } + (4/\delta )\log \upsilon + \hfill \\ + (2/\delta )\log 12 + |a| + \log (3 + 20|a|e^{|a|} )) + \log ((3/2)e^{|a|} ) + e/2\} , \hfill \\ then |e^a - p/q| 〉 q^{ - (2 + \delta )} . \hfill \\ \end{gathered} $$
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 154
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 39-48 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Consider a set of graphs and all the homomorphisms among them. Change each graph into a digraph by assigning directions to its edges. Some of the homomorphisms preserve the directions and so remain as homomorphisms of the set of digraphs; others do not. We study the relationship between the original set of graph-homomorphisms and the resulting set of digraph-homomorphisms and prove that they are in a certain sense independent. This independence result no longer holds if we start with a proper class of graphs, or if we require that only one direction be given to each edge (unless each homomorphism is invertible, in which case we again prove independence). We also specialize the results to the set consisting of one graph and prove the independence of monoids (groups) of a graph and the corresponding digraph.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 155
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 49-51 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this paperG denotes a central topologicalT 2-group—G/Z(G) compact, whereZ(G) is the center. There are some results concerning compactness of the commutator subgroupG′; in general (G′)− is compact ([3]), but not necessarilyG′ ([7]). If in additionG is a Lie group or ifG is connected,G′ is compact ([6], [5]). The purpose of this paper is to show, that if the componentG 0 of the identity is open,G′ must be compact, and to give an example of a compact group with (G/G 0)′ compact, whileG′ is not compact.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 156
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 53-58 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Let (A, ≤) be a partially ordered set, {X α} a collection of i. i. d. random variables, indexed byA. Let $$S_\alpha = \sum _{\beta \leqslant \alpha } X_\beta $$ , |α|=card {β∈A, β∈α}. We study the convergence rates ofS α/|α|. We derive for a large class of partially ordered sets theorems, like the following one: For suitabler, t with 1/2〈 〈r/t≤1:E|X| t M (|X| t/r )〈∞ andEX=μ if and only if $$S_\alpha = \sum _{\beta \leqslant \alpha } X_\beta $$ for all ε〉0, where $$M(x) = \sum _{j〈 x} d(j)$$ withd(j)=card {α∈A, |α|=j}.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 157
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 81-88 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 158
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 59-79 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this paper we consider closedB-invariant ideals in the group algebraL 1(G), whereG is a locally compact group with a relatively compact groupB of topological automorphisms, which contains the set of all inner automorphisms. We study conditions when closedB-invariant ideals are completely determined by their hull. Also questions concerning the existence of approximate units in these ideals will be answered. Above all, we shall study these properties with regard to the relations between ideals inL 1(G),L 1 (G/N) andL 1(N), whereN is a closedB-invariant subgroup ofG.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 159
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 105-113 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We study sequences (T n ) of isometries resp. affine transformations on a compact, metrizable topological group, with the property that for any uniformly distributed sequence (x n ) the sequence (T n x n ) is again uniformly distributed.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 160
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 89-97 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract The paper is concerned with the differential equation $$V_{\bar z} = C(z,\bar z)\bar V$$ with $$m^2 (\log C)_{z\bar z} + + \varepsilon C\bar C = 0,m 〉 0,\varepsilon = \pm 1$$ . The Vekua resolvents are determined by means of an associated second-order differential equation. Applications are given to pseudo-analytic functions, to a differential equation in the theory of several complex variables and to the Ernst equation in general relativity.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 161
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 99-103 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Using Selberg's sieve upper bounds for the number of primes of the formn2 n +1 withn≤x and the number of primes of the formp2 p +1 withp≤x are derived.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 162
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 115-124 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this note some questions of ideal theory for the center and more generally theB-fixed subalgebras of a Beurling algebraL ω 1 (G) are discussed. Sufficient conditions on ω are given for these subagebras to satisfy Ditkin's condition, or for primary ideals to be maximal or at least of finite codimension.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 163
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 149-162 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract LetG be a countable discrete group acting by measure-preserving automorphisms of a finite measure space (M, μ) and let $$\mathfrak{N}$$ (G,M) be the corresponding group measure space von Neumann algebra, which will be a finite von Neumann algebra. Necessary and sufficient conditions are given for $$\mathfrak{N}$$ (G,M) to have a non-zero type I part, and the projection on the type I part is explicitly described.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 164
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 125-136 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this paper sufficient conditions for the existence of equilibrium states will be given. These conditions consist of topological assumptions for the underlying system which are linked with certain analytical properties of the given continuous function ϕ. It will be shown that the setV(T) which is defined byBowen in [1] is particularly suited to guarantee the existence of maximal measures. It is possible to show the following: Let 0≤ϕ∈V(T) and ϕ(x 0)=0 wherex 0 is a fixed point of the transformationT, and let $$\mathfrak{U}$$ be a finite, open cover ofX, which satisfies. $$\mathop {lim}\limits_{n \to \infty } \frac{{Q(T^n ,S_n \varphi ,(\mathfrak{U})_0^{n - 1} )}}{n} = P(T,\varphi )$$ Then there exists an equilibrium state for the pressure function.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 165
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 137-148 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract For such curves we know a moving frame and a complete system of invariants (affine curvatures) with respect to the group of volume-conserving transformations (unimodular group) of the order 2n−1 respectively 2n (see [1], p. 171). In this paper we study for a curvec a moving frame and a system of invariants of the minimal ordern+1, respectivelyn+2, by means of a curve with vanishing affine curvatures that has contact of maximal order withc. Forn=3 this is a result ofA. Winternitz ([1], p. 171 or [3], p. 86).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 166
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 167
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 185-188 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract This article contains P.Furtwängler's method for presenting Galois theory. To any field of rational functions belongs a group of permutations and vice versa. Given a system of roots {α1, α2,..., α n } a field containing all relations existing between them can be defined. To this field belongs the Galois group of the given system.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 168
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 177-183 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We study fractional quadratic transformationsT of the sphere and try to determine their topological entropy. In the case whereT is a constant mapping or a homeomorphism, the topological entropy is of course zero. In the other cases, we have the following results. IfT has only one fixed point, its entropy is log 2. IfT has exactly two fixed points, it can be written asT z =z−z −1 +v, and ifv is real, then the entropy ofT is again log 2. A general result ofMisiurewicz andPrzytycki shows that the entropy ofT is at least log2, and we conjecture that this entropy is always equal to log2 in the remaining cases, i. e. two fixed points andv not real, and three fixed points.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 169
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 199-200 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Letn 1,n 2,...,n t integers. It is proved that the monomial congruence $$x_1^{n_1 } x_2^{n_2 } \ldots x_t^{n_t } \equiv a (\bmod m)$$ is solvable for allm≥2 and (a, m)=1 if and only if (n 1 ,n 2 ..., n t )=1.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 170
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 189-198 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract It is proved that β-shifts have unique measure with maximal entropy by constructing an isomorphism of the β-shift with another topological dynamical system and proving it for this system.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 171
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 245-252 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract For a one-parameter flow without stationary points it is proved that the notion of “quasiregular point” depends solely on the orbit structure (i. e. not on the parametrization of “time”). This leads naturally to an affine isomorphism between the cones of invariant measures before and after a continuous time change, a fact which is due toB. Marcus ([3]).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 172
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 201-210 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract There exist some useful methods for the calculation of Hilbert's function without using a free resolution of polynomial ideals (see for example [4], [10], [11] and the references in these papers). Using Bezout's theorem (in the sense ofW. Gröbner [3], 144.5) these methods are suited for a proof that special homogeneous polynomial ideals are imperfect, but not for the arithmetically Cohen-Macaulay property. It is the theorem of this paper that these gaps can be filled. This theorem therefore provides some proof that an arbitrary homogeneous polynomial ideal is perfect or imperfect. Our methods are demonstrated in three examples, taking the third example from the paper ofG. A. Reisner [7], p. 35 and, using our methods, we rather easily obtain the result of [7], that the Cohen-Macaulay property depends on the characteristic of the field. In the second example, we give some remarks on the usefulness of the definition for perfeet ideals ofF. S. Macaulay [5] (see also [6]). This also illustrates whyF. S. macaulay could only construct imperfect ideals-except such one obtainable by using ideals of the principal class.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 173
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 235-244 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract LetK andC denote, respectively, the classes of normalized convex and close-to-convex univalent functions. Associated with eachf∈C there is a collectionK (f) of functionsg∈K such thatf is close-to-convex with respect tog. A characterization ofK (f) is given in terms of the radial limits of arg {z f' (z)}, and necessary and sufficient conditions are obtained onf forK (f) to be a singleton. It is shown that for eachg∈K there is anf∈C such thatK (f)={g}. Further, a characterization is given of those functionsf for whichK (f) consists only of the half-plane mapping,g β(z)=z/(1-ze −iβ). These results are used to determine the extreme points ofC in the linear space introduced byH. Hornich (Mh. Math.73, 36–45 (1969)). It is shown that iff is an extreme point ofC, thenK (f)={g β} for some β. Finally, a geometric description is given of those functionsf∈C for whichg β∈K (f).
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 174
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 211-233 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract x 1 2 +...+x n 2 —ax 1...x n =b. First we describe a combinatorial presentation of a group of automorphisms of this equation, ifn=3, then we getPGL (2, ℤ) as such a group of automorphisms of this equation. This gives analytical applications becausePGL (2, ℤ) acts discontinously on the set {(x 1,x 2,x 3)∣0〈x 1,x 2,x 3 andx 1 2 +x 2 2 +x 3 2 −x 1 x 2 x 3=b≤0}⊂ℝ3. Further we ask for fundamental solutions of this equation. Finally, letx 1,x 2,x 3∈ℕ withx 1 x 2 2 +x 3 2 −−x 1 x 2 x 3=≤0 Then there areA, B∈SL(2, ℝ) with trA=x 1, trB=x 2 and trA B=x 3, and the group (A, B) is a discrete free group of rank two. In analysis we are interested in the question whether there are evenA, B∈SL(2, ℚ) with trA=x 1, trB=x 2 and trA B=x 3. We give necessary and sufficient conditions for that and remark that this question is connected with the ternary quadratic formk1p 2+k2q 2−r 2,k 1=x 1 2 ,k 2=16(x 2 2 +x 1 2 +x 3 2 −x 1 x 2 x 3−4), which has some invariant properties.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 175
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 259-264 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 176
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 253-258 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract modm. Ifm is natural,a an integer with (a, m)=1 put $$\begin{gathered} {}^om(a): = min\{ h\left| {h \in \mathbb{N},} \right.a^h \equiv 1(modm)\} , \hfill \\ \psi (m): = \max \{ o_m (a)\left| a \right. \in \mathbb{Z},(a,m) = 1\} , \hfill \\ g(m): = \min \{ a\left| {a \in \mathbb{N},(a,m) = 1,o_m (a) = } \right.\psi (m)\} . \hfill \\ \end{gathered} $$ Form prime,g(m) is the least natural primitive root modm. We establish the estimation $$\sum\limits_{m〈 x} {g(m)〈〈 x^{1 + \varepsilon } .} $$
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 177
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 277-282 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract n. The minimum length of sequences (x i ) of integers contained in exactlyk residue classes modn is determined with respect tox 1+...+x n ≡0 modn.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 178
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 265-276 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract For the equation $$L[u]: = K(y)u_{xx} + u_{yy} + r(x,y)u = f(x,y)$$ (K (y)⪋0 whenevery⪋0) inG, bounded by a piecewise smooth curveΓ 0 fory〉0 which intersects the liney=0 at the pointsA(−1, 0) andB(1, 0) and fory〈0 by a smooth curveΓ 1 throughA which meets the characteristic of (1) throughB at the pointP, the uniqueness of the Frankl-Morawetz problem is proved without assuming thatΓ 1 is monotone.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 179
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 283-295 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Corresponding to the case of finitely generated modules over noetherian rings we prove existence theorems for basic elements in Stein modules, and give some applications.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 180
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 297-315 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract It is well known that equivalence holds between the weak axiom of choice (AC) and the well ordering principle (WOP) for sets, resp. between strong AC and WOP for classes. It will be shown that in a theory PC* with inpredicative classes (i. e. with no restriction of quantification in the defining formula) the super-strong AC used by the informally working mathematician is equivalent to a superstrong WOP. The equivalence between strong AC and super-strong AC is implied by a conditionC refutable in PC* but provable in PC which is PC* with predicative classes only and with the general ordered pair axiom. PC* [super-strong AC] is inconsistent because the super-strong AC impliesC. Therefore the application of choice functions to non-empty classes generally makes a predicative definition of these classes necessary. Connected with these problems is a statement equivalent to the conjunction of the axioms of power set and foundation based on a function which coincides with the von Neumann-function under the assumption of one of the mentioned axioms.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 181
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 317-321 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract LetX=(X 0,X 1, ...) be a Markov chain on the discrete semigroupS. X is assumed to have one essential classC such thatC∩K≠ℓ, whereK is the kernel ofS. We study the processY=(Y 0,Y 1,...) whereY n =X 0 X 1 ...X n using the auxiliary process $$Z = \left( {\begin{array}{*{20}c} X \\ Y \\ \end{array} } \right)$$ which is a Markov chain onS×S. The essential classes and the limiting distribution of theZ-chain are determined. (These results were obtained earlier byH. Muthsam, Mh. Math.76, 43–54 (1972). However, his proofs contained an error restricting the validity of his results.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 182
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 183
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 323-336 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Some time agoTits has considered the question of characterizingB(G), and more generally, of finding the automorphisms of bounded displacement ofG, particularly whenG is a connected real Lie group. Our purpose here is to extend these results to various other cases as well as to deal with the analogous questions for 1-cocycles. We concern ourselves, among other things, with the question of sufficient conditions forB(G)=Z(G), the center, or more generally, forG to have no non-trivial automorphisms of bounded displacement. The significance of such conditions can be seen in work of the author together withF. Greenleaf andL. Rothschild where, for example, the Selberg form of the Borel density theorem is considerably generalized. These conditions are therefore closely related to, but not identical with, sufficient conditions for the Zariski density of a closed subgroupH ofG withG/H having finite volume, see [11]. For this reason it is enlightening to compare these results with those of [11]. On the cocycle level, we give sufficient conditions for the points with bounded orbit under a linear representation to be fixed and more generally, for a bounded 1-cocycle to be identically zero. These conditions actually play a role in [11]; they are among the sufficient conditions necessary to establish Zariski density ofH inG. We also deal with certain converse questions and applications to homogeneous spaces of finite volume. For example, ifG/H has finite volume and α is an automorphism ofG leavingH pointwise fixed, then α has bounded displacement. If ϕ is a 1-cocycle and ϕ/H is trivial, then ϕ is itself bounded.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 184
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 85 (1978), S. 346-348 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 185
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 1-1 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 186
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 3-6 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Given any ergodic invertible measure preserving transformation τ of [0,1] and any null-sequence (α N ) of positive reals, there exists a continuousf such that $$\lim \sup \alpha _{\rm N}^{ - 1} \left| {N^{ - 1} \sum\limits_{k = 0}^{N - 1} {f \circ \tau ^k - \smallint f} } \right| = \infty a. e.,$$ i.e. there is no “speed of convergence” in the ergodic theorem for any τ. The analogous result holds also for norm-convergence.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 187
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 7-11 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract A group (G,·) is said to be a near-field group ifG is the multiplicative group of a near-field. A near-field groupG is called hereditary if every subgroup ofG is a near-field group. This paper presents a complete characterization of finite hereditary near-field groups.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 188
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 13-62 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract It is shown that the theorem ofWeil-Cartier ([10, Th. 5], [4, Th. 3]) is connected with a homomorphism of groups of unitary operators. The existence proof for this homomorphism is based on simple results in harmonic analysis and on an extension property of the Schwartz-Bruhat functions. Some applications are given, including a result ofIgusa's [6, Th. 3] and the reciprocity formula ofKrazer-Siegel [9, Th. 2]. An outline of the proof has been given in [8].
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 189
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 63-81 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract This paper is concerned with the existence of evolution operatorsU (s, t) for Schrödinger equationsdf (t)/dt=−i H (t) f (t) with variable domainsD (H (t)) and the existence of wave operatorsW + forH (t):=−H 0+V(t). Applications to potential scattering permit also potentialsV(t) which are undamped with time.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 190
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 83-88 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 191
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 89-100 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In a class of latticesM which are invariant under an orthogonal automorphism σ vectorsx≠0 of minimal Euclidean norm are considered. To obtain the finitely many possible indices (M:ℤ[〈σ〉]x)H. W. Leopoldt's norm inequality [5] and his constantc * are used. An effective procedure for the calculation ofc * is described; some values ofc * are listed. — An application to the theory of units of algebraic number fields is mentioned.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 192
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 101-105 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract All the distributive near rings in which the index ofR′ inR is a prime have been determined. Certain d. g. near rings in whichR′ is the only normal subgroup ofR are also considered. It is also shown that if (R,+) is finite and not perfect then there is a distributive near ring in whichR 2∈0.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 193
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 131-142 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract A miquelian Laguerre-plan of characteristic ≠2 can be characterized by the property that for each pair {A, B} of non parallel points there exists an involutoric automorphism whose set of fixed points is exactly {A, B}.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 194
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 107-129 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Every Jordan pair $$\mathfrak{B} = (\mathfrak{B}^ + ,\mathfrak{B}^ - )$$ defines an algebraic varietyX containing $$\mathfrak{B}^ +$$ as a dense open subset.X is projective (affine) if and only if $$\mathfrak{B}$$ is separable (radical). The Picard group ofX is generated by the irreducible factors of the generic norm of $$\mathfrak{B}$$ . If $$\mathfrak{B}$$ is separable then the automorphism group ofX is the projective group of $$\mathfrak{B}$$ .
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 195
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 155-165 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We show that if σ is the shift on sequences of {0,1} and τ is the entropy zero transformation used by Ornstein in constructing a counter-example toPinsker's conjecture, then the skew-product transformationT defined byT(x,y)=(σx,τ x0 y) is Bernoulli. ThisT is conditionally mixing with respect to the independent generator for σ, a partition with full entropy.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 196
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 167-170 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Characterizations for subfamilies of an underlying one parametric transformation familyT are or natural interest. The paper gives an affine characterization — taking forT the area preserving plane affine motions with one finite and two infinite instantaneous centers — of the Cardan motions, by means of the higher inflection poles.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 197
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 171-176 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 198
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 143-154 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We consider random orientated straight lines in the Euclidian plane.R. Ambartzumian has pointed out that general measures of straight lines are linked with certain pseudo-metrics. He has proved that any pseudometric satisfying certain conditions is generated by a measure of straight lines. In this paper, we investigate general measures of orientated straight lines and show that they are linked with functions whose properties are similar to those of pseudo-metrics. In general, the symmetry is not given. Starting from these non-symmetric pseudo-metrics it is possible to define some sort of “length of a curve” such that the theorem ofCrofton giving the number of common points of random straight lines and fixed curves remains valid for general measures.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 199
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 203-219 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract An existence theorem for good lattice points, which was so far only available for prime moduli, is established for general moduli by using a method based on exponential sums.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 200
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Mathematik 86 (1978), S. 185-188 
    ISSN: 1436-5081
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract It is shown that everyd-dimensional zonotopeC whose vertices satisfy a certain rationality condition has the following property: There exist a positive integerk and a sequenceC 1,C 2,... of translates ofC such that every point ofd-space that is not a boundary point of someC i is in exactlyk of the setsC 1,C 2,...
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...